arch/xtensa/mm/init.c

Source file repositories/reference/linux-study-clean/arch/xtensa/mm/init.c

File Facts

System
Linux kernel
Corpus path
arch/xtensa/mm/init.c
Extension
.c
Size
5280 bytes
Lines
203
Domain
Architecture Layer
Bucket
arch/xtensa
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/memblock.h>
#include <linux/gfp.h>
#include <linux/highmem.h>
#include <linux/swap.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/mm.h>
#include <linux/of_fdt.h>
#include <linux/dma-map-ops.h>

#include <asm/bootparam.h>
#include <asm/page.h>
#include <asm/sections.h>
#include <asm/sysmem.h>

/*
 * Initialize the bootmem system and give it all low memory we have available.
 */

void __init bootmem_init(void)
{
	/* Reserve all memory below PHYS_OFFSET, as memory
	 * accounting doesn't work for pages below that address.
	 *
	 * If PHYS_OFFSET is zero reserve page at address 0:
	 * successfull allocations should never return NULL.
	 */
	memblock_reserve(0, PHYS_OFFSET ? PHYS_OFFSET : 1);

	early_init_fdt_scan_reserved_mem();

	if (!memblock_phys_mem_size())
		panic("No memory found!\n");

	min_low_pfn = PFN_UP(memblock_start_of_DRAM());
	min_low_pfn = max(min_low_pfn, PFN_UP(PHYS_OFFSET));
	max_pfn = PFN_DOWN(memblock_end_of_DRAM());
	max_low_pfn = min(max_pfn, MAX_LOW_PFN);

	early_memtest((phys_addr_t)min_low_pfn << PAGE_SHIFT,
		      (phys_addr_t)max_low_pfn << PAGE_SHIFT);

	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
	dma_contiguous_reserve(PFN_PHYS(max_low_pfn));

	memblock_dump_all();
}

static void __init print_vm_layout(void)
{
	pr_info("virtual kernel memory layout:\n"
#ifdef CONFIG_KASAN
		"    kasan   : 0x%08lx - 0x%08lx  (%5lu MB)\n"
#endif
#ifdef CONFIG_MMU
		"    vmalloc : 0x%08lx - 0x%08lx  (%5lu MB)\n"
#endif
#ifdef CONFIG_HIGHMEM
		"    pkmap   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
		"    fixmap  : 0x%08lx - 0x%08lx  (%5lu kB)\n"
#endif
		"    lowmem  : 0x%08lx - 0x%08lx  (%5lu MB)\n"
		"    .text   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
		"    .rodata : 0x%08lx - 0x%08lx  (%5lu kB)\n"
		"    .data   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
		"    .init   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
		"    .bss    : 0x%08lx - 0x%08lx  (%5lu kB)\n",
#ifdef CONFIG_KASAN
		KASAN_SHADOW_START, KASAN_SHADOW_START + KASAN_SHADOW_SIZE,
		KASAN_SHADOW_SIZE >> 20,
#endif
#ifdef CONFIG_MMU
		VMALLOC_START, VMALLOC_END,
		(VMALLOC_END - VMALLOC_START) >> 20,
#ifdef CONFIG_HIGHMEM
		PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
		(LAST_PKMAP*PAGE_SIZE) >> 10,
		FIXADDR_START, FIXADDR_END,
		(FIXADDR_END - FIXADDR_START) >> 10,
#endif
		PAGE_OFFSET, PAGE_OFFSET +
		(max_low_pfn - min_low_pfn) * PAGE_SIZE,
#else
		min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE,
#endif
		((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20,
		(unsigned long)_text, (unsigned long)_etext,
		(unsigned long)(_etext - _text) >> 10,

Annotation

Implementation Notes